Statalist


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: Polynomial OLS - Interpreting results


From   Richard Williams <Richard.A.Williams.5@ND.edu>
To   "statalist@hsphsun2.harvard.edu" <statalist@hsphsun2.harvard.edu>, "statalist@hsphsun2.harvard.edu" <statalist@hsphsun2.harvard.edu>
Subject   Re: st: Polynomial OLS - Interpreting results
Date   Tue, 30 Dec 2008 12:40:05 -0500

At 12:12 PM 12/30/2008, Claude Francoeur wrote:
Hello,

First, I would like to thank Maarten Buis and Ángel Rodríguez Laso for
their advice (see Polynomial OLS - Dec 25th).

Doing a polynomial OLS and after centering the original variable, we get
the following results :

Coefficient of X1 (the centered variable) is negative and significant;
coeff. of X1 squared is negative and not sig. and coeff. of X1 cubed is
positive and significant.

What would be the graphic representation of such a relation? Is there
only one inflexion point here (between X1 squared and X1 cubed)?

This handout might be helpful:

http://www.nd.edu/~rwilliam/stats2/l61.pdf


-------------------------------------------
Richard Williams, Notre Dame Dept of Sociology
OFFICE: (574)631-6668, (574)631-6463
HOME:   (574)289-5227
EMAIL:  Richard.A.Williams.5@ND.Edu
WWW:    http://www.nd.edu/~rwilliam


*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/



© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index